1. Technical Field
This invention relates to special wax dispersions which may be used as a basis for cosmetic preparations and, more particularly, for impregnating and wetting utility and sanitary wipes used for personal hygiene and body care.
2. Background Art
The generic term “paper” encompasses about 3,000 different types and articles which can differ, sometimes considerably, in their applications and their properties. Their production involves the use of numerous additives among the most important of which are fillers (for example chalk or kaolin) and binders (for example starch). For tissues and hygiene papers, which come into relatively close contact with the human skin, there is a particular need for an agreeable soft feel which is normally given to the paper by careful selection of the fibers and, in particular, by a high percentage of fresh mechanical wood pulp or cellulose. However, in the interests of economic paper manufacture and from the ecological perspective, it is desirable to use large amounts of inferior-quality deinked wastepaper. Unfortunately, this means that the softness of the paper is significantly reduced which is troublesome in practice and can even lead to irritation of the skin, particularly with frequent use.
Accordingly, there has been no shortage of attempts in the past to treat tissue papers by impregnation, coating or other surface treatments in such a way that a more agreeable sensory impression is achieved. This requires the development of special lotions and emulsions which, on the one hand, are easy to apply to the paper and, on the other hand, do not adversely affect its structure. Softness is often improved by the use of nonionic surfactants or a combination of nonionic and anionic surfactants. Polysiloxanes and cationic polymers are also used for this purpose.
International patent application WO 95/35411 relates to tissue papers coated with softening formulations which contain 20 to 80% by weight of a water-free emollient (mineral oils, fatty acid esters, fatty alcohol ethoxylates, fatty acid ethoxylates, fatty alcohols and mixtures thereof), 5 to 95% by weight of an “immobilizing agent” for the emollient (fatty alcohols, fatty acids or fatty alcohol ethoxylates containing 12 to 22 carbon atoms in the fatty component) and 1 to 50% by weight of surfactants with an HLB value of preferably 4 to 20. The Examples of this document all contain petrolatum as emollient. International patent application WO 95/35412 discloses similar tissue papers where water-free mixtures of (a) mineral oils, (b) fatty alcohols or fatty acids and (c) fatty alcohol ethoxylates are used as softeners. International patent application WO 95/16824 describes softening formulations for tissue papers containing mineral oil, fatty alcohol ethoxylates and nonionic surfactants (sorbitan esters, glucamides). In addition, International patent application WO 97/30216 (Kaysersberg) describes liquid softening formulations for paper handkerchiefs based on long-chain saturated fatty alcohols and wax esters with, in all, at least 24 carbon atoms which have a very high water content. DE 33 09 530 describes hygienic absorbent materials which are coated with glycerides and/or partial glycerides of coconut oil fatty acids. Coatings for personal hygiene products are also described by R. E. Mathis in Nonwovens World 1999, pages 59-65.
From the performance perspective, however, the sensory properties of the treated papers and tissues are still in need of improvement. The coatings in use at present are unsatisfactory in their skin-care effect and often leave the skin feeling too greasy and, in some cases, are distinguished by an overly slow release of active ingredients. In the field of baby hygiene in particular, the effective release of active components, an improved care effect and better sensory properties are very important requirements. The long-term stability of the coated wipes in storage is also in need of improvement. The coating should not sink to the bottom of the storage container in the event of prolonged storage. From the manufacturing perspective, the application behavior of the compositions is unsatisfactory. In particular, there is a need to develop coatings which can be applied cold and, hence, are less expensive to produce and also emit fewer odors.
The problem addressed by the present invention was to provide compositions for coating tissue papers for the production of wet wipes and dry wipes which would be distinguished by improved sensory properties and, more particularly, by a caring, non-troublesome and less greasy feeling on the skin. In addition, the compositions would be able to be applied particularly easily to substrates. The coated papers/wipes would have excellent care properties and would be distinguished by the efficient release of active components and by particular mildness and dermatological compatibility. In addition, only readily biodegradable auxiliaries would be used and the preparations would readily penetrate into the tissue, would be uniformly distributed and would be readily processable.